Ditching attachment for chain saws



July 11, 1961 A. J. HYSTER DITCHING ATTACHMENT FOR CHAIN SAWS 2 sheets sheet 1 Filed Nov. 5, 1958 INVENTOR fizz! JJYKJT R ATTORNEYS July 11, 1961 A. J. HYSTER DITCHING ATTACHMENT FOR CHAIN sAws 2 Sheets-Sheet 2 Filed Nov. 5, 1958 INVENTOR fizz J B1721 ATTORNEYS United States Patent 2,991,571 DITCHING ATTACHMENT FOR CHAIN SAWS Alex J. Hyster, RD. 1, Telegraph Road, South Amherst, Ohio Filed Nov. 5, 1958, Ser. No. 772,009 Claims. (Cl. 37-191) The present invention relates to ditching attachments for chain saws and particularly to such attachments which utilize a chain digger.

The primary object of the invention is to provide a chain digger attachment for chain saws which will convert the saw for use as a ditch digging device, digging the ditches used in laying pipe, wire, and the like.

Another object of the invention is to provide an attachment of the class described above in which the chain saw engine and frame are not modified in a material way so that the device can be converted back to chain saw use with a minimum of effort.

A further object of the invention is to provide a digging attachment for chain saws which can be easily and quickly applied to the chain saw, utilizing conventional, readily available tools.

Other objects and advantages will become apparent in the following specification when considered in the light of the attached drawings, in which:

FIGURE 1 is a perspective view of the invention;

FIGURE 2 is an enlarged fragmentary top plan view of the invention;

FIGURE 3 is an exploded perspective view of the digging chain;

FIGURE 4 is a perspective view of the shaft extension attachment; and

FIGURE 5 is a perspective view of the beam support extension.

Referring now to the drawings in detail wherein like reference characters indicate like parts throughout the several figures, the reference numeral indicates generally a chain saw having secured thereto a digging attachment, generally indicated at 11, constructed in accordance with the invention.

The chain saw 10 includes an engine 12 of conventional design having a transmission 13 extending forwardly therefrom.

In attaching the digging attachment 11 to the chain saw 10, the beam 14 and cutting saw chain (not shown) are first removed by removing the clamp plate 15 and drive sprocket 16. A dirt guard 17 is secured to the engine 12 and to the transmission 13 overlying the inner end of the beam 14 and the sprocket 16. A pair of wheels 18 are journalled on a bracket 19 which is detachably secured to the underside of the transmission 13, for reasons to be assigned. A shaft extension 20 has a cylindrical body 21 with a bore 22 extending therein. A somewhat smaller threaded bore 23 extends inwardly from the bore 22, as best shown in FIGURE 4. The cylindrical body 21 has a reduced diameter sprocket portion 24 extending axially outwardly therefrom terminating in a reduced diameter threaded portion 25. A key 26 is provided on the reduced diameter portion 24, for reasons to be assigned. A transverse threaded bore 27 extends through the cylindrical body 21 into the bore 22 to receive a set screw 28, as can be seen in FIGURE 2. The bore 22 engages over a drive shaft 29 extending into transmission 13 and the threaded bore 23 threads onto a reduced threaded extension 30, extending outwardly from the shaft 29. The set screw 28 locks the cylindrical body 21 to the shaft 29 and the sprocket 16 is engaged on the reduced diameter portion 24 with the key 26 locking the sprocket 16 against rotary movement on the reduced diameter portion 24. The conventional nut 31 locks the sprocket 16 on the reduced diameter por- 2,991,571 Patented July 11, 1961 "ice tion 24 by threading on the threaded portion 25, as can be seen in FIGURE 2. The action of the extension 20 isto move the drive sprocket 16 outwardly in spaced parallel relation to its original position.

Elongated bolts 32 are arranged in spaced parallel relation and supported in the transmission 13, replacing the shorter bolts (not shown) used in the chain saw construction of the device.

An adaptor block 33 is provided with a pair of spaced parallel bores 34 which engage over the bolts 32. The outer face of the adaptor block 33 has an oil reservoir 35 formed therein with a bore 36 extending through the block 33 communicating therewith. The block 33 has a longitudinally extending threaded bore 37 formed therein, communicating with a substantially larger bore 38 axially aligned therewith. The bore 38 intersects the side of the block 33 at 39 so that a portion of the head 40 of a bolt 41 may extend therethrough. The beam 14 of the chain saw '10 is provided with a conventional slot (not shown) which engages the head 40 of the bolt 41 so as to longitudinally adjust the beam 14 with respect to the chain saw 10. The beam 14 is engaged against the face of the block 33 and the clamping plate 15 is engaged over the bolts 32 on the opposite side of the beam 14 and clamped thereon by conventional nuts 42. The beam 14 is slotted at 43 to engage over the bolts 32 and permit its longitudinal adjustment with respect to the bolts 32.

An oil conduit 44 is connected to an oil outlet port (not shown) on the transmission 13 and has its opposite end connected to the bore 36 so that oil may be fed from the transmission 13 to the oil reservoir 35. A digging chain, indicated generally at 45, is trained over the beam '14 and over the drive sprocket 16 in a conventional manner.

The digging chain 45 has a plurality of elongated links 46 arranged in aligned relation and carrying inwardly extending integral drive teeth 47 thereon. The links 46 are the central links of the chain 45 and are arranged to be connected by a plurality of side links 48. A plurality of digging teeth 49 are secured to the side links 48 and the center links 46 by means of rivets 50. The digging teeth 49 are each provided with relatively long lateral extensions 51 having a generally upright digging portion 52 integrally formed on the outer end thereof. Additional digging teeeth 53 are provided with somewhat shorter lateral extensions 54 and integral upright digging portions 55 on their outer ends. The relatively long teeth 49 are positioned in oppositely extending pairs with the relatively short teeth 53 arranged in oppositely extending pairs separating the pairs of relatively long teeth The use of relatively long teeth 49 and relatively short teeth 53 provides a complete cut in the ditching operation so as to cleanly remove the cut and dislodged material.

The wheels 18 provide a support for the chain saw 10 during the ditching operation and permit the chain saw 10 to be pivoted thereabout as the beam 14 is lowered in the ground as the cutting begins. The wheels 18 also permit the chain saw 10 to be run along the ground as the ditching operation proceeds. It should be readily noted that the chain 45 is lubricated from the reservoir 35 with the oil passing to the reservoir 35 through the conduit 44 and the bore 36. The adjustment of the beam 14 on the block 33, by means of a bolt 41, is conventional, a similar bolt 41 being provided on the transmission 18 to adjust the beam 14 when used with the chain saw. The dirt shield 17 prevents dirt from being thrown upwardy against the operator during the ditching operation and may be readily removed when converting from the ditching operation to a chain sawing operation.

Having thus described the preferred embodiment of the invention, it should be understood that numerous structural modifications and adaptations may be resorted to without departing from the scope of the appended claims.

What is claimed is: Y

1. A ditching attachment for chain saws of the type including a transmission, a drive shaft extending outwardly from said transmission, and a chain support beam detachably secured to said transmission, comp-rising means for supporting said beam in laterally spaced relation with respect to said transmission, shaft extension means detachably secured to said shaft, said shaft extension comprising a cylindrical body having a bore therein, a smaller threaded bore extending inwardly from said first mentioned bore, a reduced diameter sprocket portion extending outwardly from said cylindrical body, a key on said sprocket portion, a reduced threaded extremity extending from said sprocket portion, a drive sprocket supported on said sprocket portion, said sprocket having a keyway engaging said key, a nut on said threaded extension securing said sprocket on said sprocket portion, and a chain trained over said support beam and said drive sprocket with said chain having a plurality of laterally extending earth digging teeth mounted thereon.

2. A device as claimed in claim 1 wherein the means supporting said beam in spaced relation to said transmission includes an adaptor block having a bolt receiving bore therethrough and a lubricating oil reservoir formed therein and means connecting said reservoir to said transmission for feeding lubricating oil from said transmission to said reservoir, said support beam having a slot there in, and a bolt extending through said slot and said bore for supporting said beam.

3. A device as claimed in claim 2 wherein a dirt guard is detachably secured to said transmission in overlying relation to said beam and said sprocket.

4. A device as claimed in claim 3 wherein a pair of support Wheels are journalled to said transmission in underlying relation to said beam.

5. A device as claimed in claim 4 wherein said digging teeth are provided with laterally extending portions terminating in integral upright portions formed thereon.

References Cited in the file of this patent UNITED STATES PATENTS 1,067,328 Ferriss July 15, 1 913 1,886,382 Dunlap Nov. 8, 1932 2,348,588 Arseneau May 9, 1944 2,718,908 Kiekhaefer Sept. 27, 1955 2,748,810 Strunk June 5, 1956 2,783,794 Kroll Mar. 5, 1957 2,821,216 West et a1 Jan. 28, 1958 2,835,055 Hermes May 20, 1958 FOREIGN PATENTS 88,674 Norway Jan. 28, 1957 

